1. Technical Field
Aspects of this document relate generally to telecommunication systems and techniques for transmitting data across a telecommunication channel.
2. Background Art
In digital communication receivers employing M-ary PSK or M-ary QAM, carrier frequency estimation is commonly accomplished using Fast Fourier Transform (FFT) together with modulation removal. The frequency acquisition range using FFT is limited to the FFT search bandwidth (SBW). If the carrier frequency offset (Fo) is beyond SBW but within 2*SBW (i.e. receiver acquisition range is twice the SBW), then the time duration to estimate the frequency will be doubled because it will take at least two sequential FFT operations given that the FFT sampling rate is unchanged. Thus, using currently existing methods and systems, carrier acquisition requires a longer time duration than may be desirable in some applications.
To reduce the length and complexity of the detailed description and to establish a current state of the art, Applicant hereby incorporates by reference in their entirety each reference listed in the numbered paragraphs below:
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